Refits of in-space vessels should be done at EML-1 (or maybe EML-2). Easily accessed from Earth, Moon, interplanetary, minimal energy to maintain position, top of gravity well for departure (w/ Oberth burn advantages). In-spac ship assembly could also be done here -- avoids ships having to be structurally strong enough (and small enough) to depart Lunar surface as well as eliminating the delta-v penalty discussed above.

Yes, minor refits and normal maintenance could be done at EML-1/2 but mind you that would require a large facility orbiting the Lagrange point. That's a big deal. Why have a surface base and a big orbiting shipyard? Being structurally strong enough to to depart the lunar surface is a good thing. Even the Apollo LM's did that so that's not a big deal. The only reason we do on-orbit assembly is because we can't lift enough mass in a single lift to build it on the ground. That would not be the case in lunar gravity. What could we put in LEO if our engines were 6 times as powerful as they are now and only had to go 43% the altitude (98 km vs 250 km) and only 22% the velocity (5,800 k/h vs 27,360 k/h) to orbit? That's the lift advantage the lunar surface offers. Think big AncientU, think big.

« Last Edit: 03/12/2017 11:23 AM by clongton »

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Chuck - DIRECT co-founderI started my career on the Saturn-V F-1A engine

Refits of in-space vessels should be done at EML-1 (or maybe EML-2). Easily accessed from Earth, Moon, interplanetary, minimal energy to maintain position, top of gravity well for departure (w/ Oberth burn advantages). In-spac ship assembly could also be done here -- avoids ships having to be structurally strong enough (and small enough) to depart Lunar surface as well as eliminating the delta-v penalty discussed above.

Yes, minor refits and normal maintenance could be done at EML-1/2 but mind you that would require a large facility orbiting the Lagrange point. That's a big deal. Why have a surface base and a big orbiting shipyard? Being structurally strong enough to to depart the lunar surface is a good thing. Even the Apollo LM's did that so that's not a big deal. The only reason we do on-orbit assembly is because we can't lift enough mass in a single lift to build it on the ground. That would not be the case in lunar gravity. What could we put in LEO if our engines were 6 times as powerful as they are now and only had to go 43% the altitude (98 km vs 250 km) and only 22% the velocity (5,800 k/h vs 27,360 k/h) to orbit? That's the lift advantage the lunar surface offers. Think big AncientU, think big.

EML1 is better location for constructing large space assets. Not constrained by gavity, LV and Lander requirements. Have moon or asteriods provide processed materials and simple but heavy parts with earth providing high tech parts.

I would suggest that the eventual goal would be a functioning interplanetary exploration center and shipyard, where interplanetary spacecraft are built, launched, recovered, refurbished, restocked, re-crewed and launched again. Absence of the deep earth gravity well will eventually enable far more efficient spacecraft designs that what we can build on earth, work real hard to put tiny pieces of it into LEO and then assemble in zero-g. Fighting only only 1/6 g it shouldn't be much problem to outfit engines strong enough to lift the vehicles into LLO before mission departure.

This is, of course, a long term vision, but one that I believe, if you think long term, is practical.

Well, since you've raised the issue.

I think lunar material should be mined, and artillery 'shells' should be manufactured on the moon. A giant cannon will fire the shell on a suborbital trajectory. Drones in low lunar orbit, will intercept the 'shells', and accelerate it up to low lunar orbit velocity. I don't know if the cannon will be a railgun, light gas gun, or liquid propellant combustion. battleship cannons would get ~800 m/s. AA autocannons get around ~1,100 m/s. Tank sabot rounds can get around ~1,500 m/s. The Paris Gun got ~1,600 m/s. HARP once got over ~2,000 m/s. I guess there are tradeoffs on barrel longevity, payload size, etc. Low Lunar orbit is ~1,800 m/s. I will assume ~1,100 m/s is the low end velocity with reasonable barrel life. Hydrogen will be brought from earth, to produce silane and oxygen rocket fuel.

shipyards should be built in low lunar orbit. I can see ship size of tens of thousands of tons... I anticipate the desired delta v to be enough to do a gravity assist swing by of Venus to reach Jupiter, Saturn, or beyond. Yes, that is going to need lots of silane. 2000? 3000? m/s from LLO to Venus gravity assist flyby. I imagine it will be a nuclear power station with food grow room. I imagine it will be like the Nimitz class aircraft carriers.

All that silicon dioxide rocket exhaust should be shot at the moon, lest it trash up lunar orbit.

Refits of in-space vessels should be done at EML-1 (or maybe EML-2). Easily accessed from Earth, Moon, interplanetary, minimal energy to maintain position, top of gravity well for departure (w/ Oberth burn advantages). In-spac ship assembly could also be done here -- avoids ships having to be structurally strong enough (and small enough) to depart Lunar surface as well as eliminating the delta-v penalty discussed above.

Yes, minor refits and normal maintenance could be done at EML-1/2 but mind you that would require a large facility orbiting the Lagrange point. That's a big deal. Why have a surface base and a big orbiting shipyard? Being structurally strong enough to to depart the lunar surface is a good thing. Even the Apollo LM's did that so that's not a big deal. The only reason we do on-orbit assembly is because we can't lift enough mass in a single lift to build it on the ground. That would not be the case in lunar gravity. What could we put in LEO if our engines were 6 times as powerful as they are now and only had to go 43% the altitude (98 km vs 250 km) and only 22% the velocity (5,800 k/h vs 27,360 k/h) to orbit? That's the lift advantage the lunar surface offers. Think big AncientU, think big.

Factories for spaceships on the Moon make sense, but assembling them at EML-1 will be necessary -- since my spaceships are thousands (then, after a bit of practice, millions) of tonnes and never 'land.' Our biggest engines would be kept quite busy.

All have artificial gravity and are meant for long duration space travel -- Solar System first.One day... starships, O'Neill cylinders.

Note: the 'large facility orbiting the Lagrange point' would be one of many construction shacks.

« Last Edit: 03/12/2017 03:58 PM by AncientU »

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"If we shared everything [we are working on] people would think we are insane!"-- SpaceX friend of mlindner

COLORADO SPRINGS — With NASA’s long-term strategy for human missions to Mars in flux, heads of several space agencies said they supported initial missions to the moon as a key step before going to Mars.

During an April 4 panel session during the 33rd Space Symposium that featured representatives from 15 agencies, many expressed support for going to Mars only after building up experience at the moon first.

“We think that the moon is also a very important step. Mars is not the ultimate goal,” said Jan Woerner, director general of the European Space Agency. “The moon is an intermediate step to go to Mars, but the moon can also offer some special opportunities.”

Woerner, as he has done in recent years, promoted his vision for a “Moon Village,” a lunar facility that would include contributions from various countries and companies. “Moon Village is part of our overall strategy,” he said.

COLORADO SPRINGS — With NASA’s long-term strategy for human missions to Mars in flux, heads of several space agencies said they supported initial missions to the moon as a key step before going to Mars.

During an April 4 panel session during the 33rd Space Symposium that featured representatives from 15 agencies, many expressed support for going to Mars only after building up experience at the moon first.

“We think that the moon is also a very important step. Mars is not the ultimate goal,” said Jan Woerner, director general of the European Space Agency. “The moon is an intermediate step to go to Mars, but the moon can also offer some special opportunities.”

Woerner, as he has done in recent years, promoted his vision for a “Moon Village,” a lunar facility that would include contributions from various countries and companies. “Moon Village is part of our overall strategy,” he said.

COLORADO SPRINGS — With NASA’s long-term strategy for human missions to Mars in flux, heads of several space agencies said they supported initial missions to the moon as a key step before going to Mars.

During an April 4 panel session during the 33rd Space Symposium that featured representatives from 15 agencies, many expressed support for going to Mars only after building up experience at the moon first.

“We think that the moon is also a very important step. Mars is not the ultimate goal,” said Jan Woerner, director general of the European Space Agency. “The moon is an intermediate step to go to Mars, but the moon can also offer some special opportunities.”

Woerner, as he has done in recent years, promoted his vision for a “Moon Village,” a lunar facility that would include contributions from various countries and companies. “Moon Village is part of our overall strategy,” he said.

I don't think NASA will be landing humans or building lunar bases anytime soon, at least until DSG is operational. But robotic exploration and pilot ISRU plants are likely with commercial backing in early 2020s.

http://www.thespaceshow.com/recent-shows13july Dr Mike GriffinWould like to see lunar base along with focusing on ISRU especially oxygen extraction for fuel and life support. While being primary government lead/funded wants commercial involvement eg coms, power, cargo providers, ISRU

COLORADO SPRINGS — With NASA’s long-term strategy for human missions to Mars in flux, heads of several space agencies said they supported initial missions to the moon as a key step before going to Mars.

During an April 4 panel session during the 33rd Space Symposium that featured representatives from 15 agencies, many expressed support for going to Mars only after building up experience at the moon first.

“We think that the moon is also a very important step. Mars is not the ultimate goal,” said Jan Woerner, director general of the European Space Agency. “The moon is an intermediate step to go to Mars, but the moon can also offer some special opportunities.”

Woerner, as he has done in recent years, promoted his vision for a “Moon Village,” a lunar facility that would include contributions from various countries and companies. “Moon Village is part of our overall strategy,” he said.

The US should adopt a policy of "Lunar COTS" at 7% of NASA's budget for a lunar program involving full-sized landers (e.g. Masten Xeus & ULA ACES-DTAL). It should also fund the delopement of ice-harvesting telerobots and a large, flat-roofed, inflatable, surface habitat. The IS should then urge other countries to fund their own companies to develop dissimilar, redundant components of the transportation, ice-harvesting, and habitation systems.

The US should adopt a policy of "Lunar COTS" at 7% of NASA's budget for a lunar program involving full-sized landers (e.g. Masten Xeus & ULA ACES-DTAL).

That is the "how" to get something done, but not the "why". Why should the U.S. Government do that?

Does it satisfy a political need, and if so what?

Does it satisfy a national security need, and if so what?

Is it part of our nations continuing (but declining under Trump) desire to fund "science" because we know it has long-term payoffs? And if so, what is the rationale?

We in the space community are good at thinking up solutions, but we don't lack solutions, we lack a compelling reason for the U.S. Government to spend taxpayer money on doing this. What is the reason Congress will want to spend money on this, for decades to come?

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If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

NASA fund lunar exploration and maybe small harvesting demo but after that it should be purely commercial venture. If NASA wants to purchase lunar fuel or water and have delivered to set destination eg DSG all better.

I think yes, it should. There are many reason, but an important one is that, while there's no solid business case for Mars at this moment, there are solid business cases for returning to and start exploiting the Moon with reasonable funding and reasonable expectations of return. NASA (and other public space agencies) can't do everything but should encourage private industry to step in.

I think yes, it should. There are many reason, but an important one is that, while there's no solid business case for Mars at this moment, there are solid business cases for returning to and start exploiting the Moon with reasonable funding and reasonable expectations of return. NASA (and other public space agencies) can't do everything but should encourage private industry to step in.

As in most other business cases like what you are referencing is that they are all dependent on NASA being the anchor customer. And that the business cases all make assumptions as to how big that buy in by NASA will be. They could be right and they could be wrong ($0 funding).

The future is not as dim as I seem to paint it, because those that do get started will find some commercial customers. While the gov customer sales may not increase the commercial customer market will grow once the service/product is established and offers a less expensive path to achieving the customers goals. It is that getting established part that seemingly takes decades in this government controlled activities environment.

You want to be inspired by things. You want to wake up in the morning and think the future is going to be great. That's what being a spacefaring civilization is all about. It's about believing in the future and believing the future will be better than the past. And I can't think of anything more exciting than being out there among the stars.

If BFR is ready by 2022 then NASA should send cargo by commercial , crew one or two years later. Then cargo to Mars by 2024 and crew by 2030.A little late for CxP timing for Lunar but could be back on track for crew for Mars.

If NASA pays SX for BFS landing on Lunar then SX could possible then afford to send BFS to Mars. It is a matter of how much NASA would pay. Even if NASA payed $500M for each landing that would be cheaper than SLS with NASA Lunar lander. A bargain for NASA and good enough that that would pay for the BFS and the sortie to Lunar and a trip to Mars.

If BFR is ready by 2022 then NASA should send cargo by commercial , crew one or two years later. Then cargo to Mars by 2024 and crew by 2030.A little late for CxP timing for Lunar but could be back on track for crew for Mars.

If NASA pays SX for BFS landing on Lunar then SX could possible then afford to send BFS to Mars. It is a matter of how much NASA would pay. Even if NASA payed $500M for each landing that would be cheaper than SLS with NASA Lunar lander. A bargain for NASA and good enough that that would pay for the BFS and the sortie to Lunar and a trip to Mars.

In the unlikely event that SX is close to their BFR in service timeline to land a couple of BFS on Mars in 2022. Which means the BFR system will be flying in the 2020 to 2021 period. The temptation for the current POTUS to have boots on the Moon with a ride from SX will be too great.

Vice President Pence Calls for Human Missions to Moon, Mars at National Space Council

NASAPublished on Oct 5, 2017

Vice President Mike Pence called for returning U.S. astronauts to the Moon and eventual missions to Mars during the first meeting of the National Space Council, held on October 5 at the Smithsonian National Air and Space Museum’s Steven F. Udvar-Hazy Center, outside Washington. Chaired by the Vice President, the council meeting brought together representatives from all aspects and sectors of the national space enterprise, for the first time in a quarter-century. NASA’s Acting Administrator, Robert Lightfoot was among the participants.

If BFR is ready by 2022 then NASA should send cargo by commercial , crew one or two years later. Then cargo to Mars by 2024 and crew by 2030.A little late for CxP timing for Lunar but could be back on track for crew for Mars.

If NASA pays SX for BFS landing on Lunar then SX could possible then afford to send BFS to Mars. It is a matter of how much NASA would pay. Even if NASA payed $500M for each landing that would be cheaper than SLS with NASA Lunar lander. A bargain for NASA and good enough that that would pay for the BFS and the sortie to Lunar and a trip to Mars.

Are you implying NASA will develop a way to land crew on the Moon by 2023-2024, since this is the earliest SLS/Orion could carry crew on EM-2? Same question about Mars 6 years later?

IMO, if/when BFS lands cargo on the Moon, the crewed flights on BFS will only be 6-12 months behind.

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"If we shared everything [we are working on] people would think we are insane!"-- SpaceX friend of mlindner

If BFR is ready by 2022 then NASA should send cargo by commercial , crew one or two years later. Then cargo to Mars by 2024 and crew by 2030.A little late for CxP timing for Lunar but could be back on track for crew for Mars.

If NASA pays SX for BFS landing on Lunar then SX could possible then afford to send BFS to Mars. It is a matter of how much NASA would pay. Even if NASA payed $500M for each landing that would be cheaper than SLS with NASA Lunar lander. A bargain for NASA and good enough that that would pay for the BFS and the sortie to Lunar and a trip to Mars.

Are you implying NASA will develop a way to land crew on the Moon by 2023-2024, since this is the earliest SLS/Orion could carry crew on EM-2? Same question about Mars 6 years later?

IMO, if/when BFS lands cargo on the Moon, the crewed flights on BFS will only be 6-12 months behind.

2024 is when ULA hopes to fly the ACES upper stage to the Vulcan launch vehicle. With a modification kit from Masten this becomes the XEUS lunar lander. The dates fit nicely.